1. Field of Invention
The present invention is directed to a method and apparatus utilizing a portable device including a replaceable cover. In particular, the present invention relates to a hand-held portable device including a replaceable housing and an array sensor.
2. Description of Related Art
Presently, mobile communication devices and hand held portable devices such as mobile phones, pagers, portable games, remote controls, and the like, provide communication and other functionality for users on the go. For example, a user with a mobile phone or a user with a portable game can use these devices while in a car. Also, enhanced applications on portable devices are increasing in popularity. For example, mobile phones may include personal organizer applications, Internet access applications, messaging applications, gaming applications, phone book applications, or the like. Unfortunately, the enhanced applications may require inputs exceeding the available inputs on the device. For example, typical numeric keypads are not easily useful for gaming purposes. Also, the limited surface area of a mobile communication device limits the number of inputs that can be added to the mobile communication device. For example, a full personal computer keyboard cannot be added to a mobile communication device without limiting its portability. Thus, mobile communication devices do not provide adequate inputs for enhanced applications.
Furthermore, portable device input functionality is becoming increasingly complex. For example, additional applications may require additional keys, dials, buttons, or the like for efficient operation. In particular, scrolling buttons may be located on the face of a portable device to allow a user to scroll through options on a display. Other examples include volume control buttons, option selection buttons, voice memo keys, or the like. Unfortunately, these additional keys can clutter the face of a portable device making the portable device difficult to use. Furthermore, the limited space on the face of the portable device limits the number of additional input devices that can be added to the portable device. Additionally, the additional input devices can reduce the ability of an inexperienced user to understand the operation of the portable device. Accordingly, these mobile communication devices also do not provide adequate user input features.
Capacitive-based touch pads are disclosed in U.S. Pat. No. 5,565,658, issued on Oct. 15, 1996 to Gerpheide et al., U.S. Pat. No. 5,861,875, issued on Jan. 19, 1999 to Gerpheide, and U.S. Pat. No. 6,222,528 B1, issued on Apr. 24, 2001 to Gerpheide et al. These touch pads are disclosed as being a replacement for a mouse on both laptop and desktop computers. In particular, these touch pads are disclosed as being particularly useful as replacement pointing devices on computers utilizing full keyboards and displays such as monitors or large LCD displays. Unfortunately, such computers are not useful as mobile communication devices because of their limited portability. In particular, full keyboards, monitors, and even laptop computers are cumbersome to conveniently carry on a person. Another problem exists in that the touch pads take up a relatively large amount of surface area in addition to the keyboards and displays. Thus, the touch pad may add to the inconvenience of carrying a device that the touch pad is attached to when the touch pad is included along with a full keyboard and display.
Therefore, there is a need for a means for convenient data entry for enhanced applications on a portable device.